Source: Healio Interviews
Disclosures: LaMattina reports no relevant financial disclosures.
April 15, 2021
5 min read

Q&A: Rethinking single-use plastics in ophthalmology

Source: Healio Interviews
Disclosures: LaMattina reports no relevant financial disclosures.
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Health care is one of the most carbon-intensive service sectors in Western industrialized countries, responsible for 4.4% of global greenhouse gas emissions.

In the U.S., health care is estimated to contribute 8% to 10% of the national carbon footprint. The wide adoption of disposable medical equipment and consequent production of large amounts of solid waste, particularly plastics, account for a large share of the total emissions in this sector.

Kara C. LaMattina, MD
Kara C. LaMattina

Disposables save time and may reduce the risk for infection, but the environmental impact and increased cost may not outweigh the benefits, according to a study published in Journal of Glaucoma. The authors showed that the use of disposable tonometer prisms and gonioscopy lenses at their institution, Boston Medical Center (BMC), produces an excess $65,185 spent yearly, with 109.6 kg of plastic waste that could be avoided by adopting reusable devices.

Ocular Surgery News interviewed Kara C. LaMattina, MD, one of the study authors. Currently an assistant professor at Boston University School of Medicine and BMC, LaMattina has a diverse professional background — with time spent working in Central and South America, Africa and India — that has led her to develop a strong interest in global health and sustainable, environmentally friendly medicine.

OSN: In the past decade, we have become increasingly aware of the extraordinary amount of waste produced by our health care systems and the impact it has on the global emission of greenhouse gases. How does ophthalmology contribute to this burden?

LaMattina: Ophthalmology practices, both in the operating room and in the clinic, rely widely on single-use plastics. In our study, we focused on the use of disposable tonometer prisms and gonioscopy lenses, which are only two small pieces of diagnostic equipment, and yet the amount of plastic waste they produce in 1 year is striking. The shift toward disposables was driven by well-justified concerns about infection from contaminated instruments. However, current available data show that reusable instruments are equally safe as long as they are properly disinfected with diluted bleach or alcohol.

During my years abroad, I had the chance to see that reusable instruments, when proper hygiene and disinfection protocols are followed, are just as safe, less costly and more eco-friendly. For 1 month I was at Aravind Eye Hospital in India, and that experience was an eye-opener for me. It changed my entire perspective on how we deliver health care. It made me realize that reducing the carbon footprint of health delivery is possible and should be set as a goal for ourselves and our country. We are buying electric cars, and yet we are still throwing out and piling on in landfills a lot of our waste.

OSN: In your study, you quantify the economic environmental burden of single-use vs. reusable tonometer prisms and gonioscopy lenses. What were your findings in terms of costs?

LaMattina: BMC is an urban hospital that serves the greater Boston area. In the ophthalmology clinic, approximately 64,000 visits are performed per year, and this includes 14,000 glaucoma visits during which applanation tonometry and gonioscopy are performed. Between 2017 and 2019, an average of 61,115 disposable prisms and 800 disposable lenses were purchased per year, generating an average total cost of about $70,000 and $9,000 per year, respectively. We compared these costs with the hypothetical scenario in which non-disposable instruments are used, calculating a 50% yearly replacement rate and incorporating the added cost of disinfection with diluted bleach plus the cost of time spent on disinfection. We found that, overall, the use of disposable prisms and lenses results in an excess of approximately $65,000 per year.

OSN: How did you measure the environmental impact, and what were your findings?

LaMattina: Basically, we looked at the amount of plastic waste generated by disposable prisms and lenses and found that it amounts to approximately 100 kg per year. That is how much one institution produces for just gonioscopy and tonometry, and if you multiplicate this number by the number of institutions across the country that are using these disposable pieces of equipment, you end up with a much greater impact overall. In a single decade, 100 similar institutions produce more than 120 tons of plastic waste. Plastics accumulate in landfills and oceans. Microplastic particles are accumulating over long distances, produce toxins, enter the food chain and kill wildlife.

OSN: Do you think that ophthalmologists should consider relying more on reusable equipment?

LaMattina: I think that industries and medical professionals, including ophthalmologists, should become more aware of the consequences of using disposables. If we compromise long-term sustainability for short-term benefits and do not take into account the larger environmental impact, we will end up paying a much higher price in the long term.

I had the pleasure of joining an expedition team looking at microplastics in the Arctic sea, and when you see how far these plastics travel and the damage they are causing to the polar ecosystems, you start realizing the long-lasting impact of your behaviors. It might be more convenient and time-saving to just pop something on and then throw it away, but the environmental consequences cannot, at this point in time, be underestimated. Industries across the world are beginning to reassess their environmental impact, and health care should not be an exception. We need therefore to consider more closely if the risk for transmitting infections is real with specific instruments when appropriate, stringent reprocessing protocols are followed.

OSN: The COVID-19 pandemic has increased the need to protect patients and health care personnel from infection, and the massive use of disposable personal protective equipment (PPE) has increased the amount of waste produced by clinics. Is an eco-friendly approach compatible with the current situation?

LaMattina: Interestingly, COVID has made us adopt creative solutions and discover that we can reuse certain products in certain ways. Because of shortage in the supply chain of PPE, at BMC we have developed a protocol for reusing our N95 masks. With COVID, we have seen that transmission can occur through ophthalmology exams, we know that tears carry the virus, and we know what kills this virus, so we know what extra precautions we have to take. We must tailor our approach to the individual pathogen, adopting practices based on evidence, primarily on what we find through laboratory testing.

The most common organisms reported for infection following applanation tonometry and gonioscopy are adenovirus and herpes simplex virus, but potentially, though rarely, also hepatitis C and B viruses and the prion of Creutzfeldt-Jakob disease. What we need to do is grade the risk for transmission of these pathogens, test their survival on surfaces, learn what sanitation techniques work to destroy them and consequently develop the appropriate protocols. We need a more directed, targeted approach rather than just use disposable plastics because we do not want to take any risk. There is now a generation of our trainees that are really concerned about climate change and the long-term implications of what we are doing at present. Their motivation hopefully will be the driving force in the transition to an environmentally sustainable health system.